Heat exchanger and method of manufacturing the same

ABSTRACT

A heat exchanger includes a connector for connecting a header tank to an exterior pipe. The connector includes a first member configured to define a communication path through which a tank open portion of the header tank communicates with an interior of the exterior pipe, and a second member to which the first member is fixed. The first member and the second member are fixed to each other after being separately formed by pressing, and the second member has a fastening portion through which the connector is fastened to the exterior pipe. Furthermore, the first member includes a first connection portion that is fitted into the tank open portion at one open side of the communication path, and a second connection portion fitted to an open portion of the exterior pipe at other open side of the communication path.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2007-070149 filed on Mar. 19, 2007, the contents of which are incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a heat exchanger having a connector for connecting a header tank to an exterior pipe, and a method of manufacturing a heat exchanger.

2. Description of the Related Art

A conventional heat exchanger includes a plurality of tubes in which a fluid flows, a header tank located to communicate with the tubes, and a connector for fixing a pipe to be connected. The connector has therein a communication hole portion for communicating an interior of the header tank with the pipe to be connected (e.g., JP-A-2003-314988).

A first connection portion of the connector, in which the pipe is inserted, is formed in the connector at one open side of the communication hole portion, and a second connection portion of the connector is formed in the connector at the other open side of the communication hole portion. The second connection portion is inserted and fitted into a connection port of the header tank. Accordingly, in order to air-tightly connect the header tank and the pipe by using the connector, it is necessary to accurately perform cutting process for forming the first and second connection portions in the connector.

The inventors of the present application have made a single connector having first and second connection portions 1 and 2 shown in FIGS. 10 and 11 for studying the cutting process of the connector. In the example of the connector shown in FIGS. 10 and 11, an inner surface 2 and a flare portion 3 of the first connection portion 1 are necessary to be formed by cutting, and a top end surface 6 and outer surfaces 4, 7, 8, 9 of the second connection portion 5 are necessary to be formed by cutting. In this case, because a large number of surfaces are formed by cutting, manufacturing efficiency of the heat exchanger is deteriorated.

SUMMARY OF THE INVENTION

In view of the foregoing problems, it is an object of the present invention to provide a heat exchanger, which can effectively improve production efficiency.

It is another object of the present invention to provide a heat exchanger, which can effectively improve the production efficiency while connection portions can be air-tightly connected.

It is another object of the present invention to provide a method of manufacturing a heat exchanger, which can effectively improve manufacturing efficiency.

According to an aspect of the present invention, a heat exchanger includes: a plurality of tubes in which a fluid flows, the tubes being arranged in parallel with each other; a header tank located at one end side of the plurality of tubes in a longitudinal direction of the tubes to distribute the fluid into the tubes and to join the fluid from the tubes; and a connector. The connector includes a first member configured to define a communication path through which a tank open portion of the header tank communications with an interior of an exterior pipe, and a second member to which the first member is fixed. In the heat exchanger, the first member and the second member are fixed to each other after being separately formed by pressing, and the second member has a fastening portion through which the connector is fastened to the exterior pipe. Furthermore, the first member includes a first connection portion that is fitted into the tank open portion at one open side of the communication path, and a second connection portion fitted to an open portion of the exterior pipe at other open side of the communication path.

Because the connector is constructed of the first member and the second member having the above structure, the connector can be formed without a cutting process, thereby improving production efficiency of the heat exchanger.

For example, the second member may have a through hole into which the second connection portion of the first member is fitted by expanding the second connection portion to the first member, or/and the first connection portion of the first member may be brazed to the tank open portion of the header tank to be fixed to the tank open portion of the header tank. Furthermore, the first connection portion of the first member may be a cornuted pipe, and the second connection portion of the first member may be a circular pipe.

Alternatively, the second connection portion of the first member may be located to be fitted into the open portion of the exterior pipe, the second connection portion may include a flare portion at an end portion in an axial direction, and the flare portion may extend radially outwardly as toward to the other open side of the communication path in the axial direction. Furthermore, the second connection portion of the first member may further include a flange portion extending outwardly in a radial direction from the flare portion, and the second member may have a flange supporting portion configured to support the flange portion in a direction parallel to the axial direction. The flange portion may have a flat surface at the other open side of the communication path in the axial direction, and the second member may have a flat surface at the other open side of the communication path in the axial direction. In this case, the flat surface of the flange portion may have a surface direction that corresponds to that of the flat surface of the flange portion.

The second member may have an inner peripheral end surface at the other end side in the axial direction, and the inner peripheral end surface may be located to enclose the flange portion of the second connection portion of the first member in a direction perpendicular to the axial direction. In this case, the flange portion may have a radial outward end portion that is opposite to the inner peripheral end surface of the second member and is spaced from the inner peripheral end surface of the second member by a clearance.

In the heat exchanger, the second member may have an inner peripheral surface portion for defining the through hole. In this case, one of a recess portion and a protruding portion may be provided at the inner peripheral surface portion of the second member, the other one of the recess portion and the protruding portion may be provided at an outer peripheral portion of the first member, such that the protruding portion is fitted into the recess portion. Furthermore, a seal member may be located at the inner peripheral surface portion of the second connection portion of the first member to seal between the inner peripheral surface portion of the second connection portion and the exterior pipe, and the one of the recess portion and the protruding portion may be located at a position shifted from the seal member in the axial direction.

In the heat exchanger, for example, the exterior pipe may be provided for supplying the fluid to the header tank or for discharging the fluid from the header tank, and the tubes may be arranged such that the fluid flowing in the tubes is heat exchanged with an exterior fluid outside the tubes.

According to another aspect of the present invention, a method of manufacturing a heat exchanger includes forming a header tank to be connected to one end side of a plurality of tubes in a longitudinal direction of the tubes, and forming a connector. Furthermore, the forming of the connector includes: forming a first member having a first connection portion and a second connection portion by pressing; forming a second member having a through hole by pressing; inserting the second connection portion of the first member into the through hole and expanding the second connection portion by using a jig to the first member, forming a flare portion by pressing at an end portion of the second connection portion of the first member, and forming a flange portion at a position radially outside of the flare portion by pressing. Furthermore, the method includes fitting the first connection portion of the first member to a tank open portion of the header tank.

Because the first member and the second member are fitted to form the connector after the first member and the second member of the connector are formed respectively without using a cutting process, the manufacturing efficiency of the heat exchanger can be effectively improved.

For example, the flange portion may be formed by pressing to have a flat surface, the second member may be formed to have a flat surface, and the first member may be fitted to the second member such that a surface direction of the flat surface of the flange portion corresponds to a surface direction of the flat surface of the flange portion. Furthermore, the first member may be fitted to the second member such that an inner peripheral end surface of the second member encloses the flange portion of the second connection portion of the first member in a direction perpendicular to the axial direction, and the flange portion may have a radial outward end portion that is opposite to the inner peripheral end surface of the second member and is spaced from the inner peripheral end surface of the second member by a clearance. In this case, the flange portion can be easily accurately formed by pressing without bending.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional objects and advantages of the present invention will be more readily apparent from the following detailed description of preferred embodiments when taken together with the accompanying drawings. In which:

FIG. 1 is a front view showing a condenser (heat exchanger) according to a first embodiment of the present invention;

FIG. 2 is a perspective view showing a connector for the condenser in FIG. 1;

FIG. 3 is a sectional view showing a connector for the condenser in FIG. 1;

FIG. 4 is a sectional view showing a body portion of the connector of the condenser in FIG. 1;

FIG. 5 is an enlarged view showing a part of the connector shown in FIG. 3;

FIG. 6 is a flow diagram showing a manufacturing process of the connector according to the first embodiment;

FIG. 7 is a flow diagram showing a process in the manufacturing process shown in FIG. 6;

FIG. 8 is a partially sectional view showing a connector for a heat exchanger according to a second embodiment of the present invention;

FIG. 9 is a perspective view showing a body portion of the connector according to the second embodiment;

FIG. 10 is a front view showing a connector in a related art; and

FIG. 11 is a bottom view showing the connector in FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

A first embodiment of the present invention will be described with reference to FIGS. 1 to 7. In this embodiment, a heat exchanger of the present invention is typically used as a condenser 100 for cooling and condensing refrigerant in a refrigerant cycle device for a vehicle.

As shown in FIG. 1, the condenser 100 includes components such as a core portion 110, a left header tank 120, a right header tank 130, cover members 140, and a receiver 150. The components of the condenser 100 are made of aluminum or an aluminum alloy, and are assembled by fitting and fastening by using a jig. The temporally assembled components of the condenser 100 can be brazed and integrated by using a brazing material applied to a surface of each component beforehand.

The core portion 110 includes a plurality of tubes 111 in which a fluid (e.g., refrigerant) flows, and a plurality of corrugated fins 112. The tubes 111 are arranged in parallel, and the tubes 111 and the corrugated fins 112 are alternatively stacked to each other in a stack direction that is perpendicular to a longitudinal direction of the tubes 111. Two side plates 113 each having an approximately U-shaped cross section are located at two ends of the core portion 110 in the stack direction so as to reinforce the core portion 110. For example, the two side plates 113 are connected to the corrugated fins 112 at outermost sides, respectively, in the stack direction

In the example of the condenser 100 shown in FIG. 1, the core portion 110 is arranged such that the tubes 111 extend in a horizontal direction. Therefore, the two side plates 113 are located at the top and bottom portions of the core portion 110, and refrigerant flows through the tubes 111 approximately horizontally.

The core portion 110 is a heat exchanging portion in which the refrigerant flowing in the tubes 111 is heat exchanged with air (outside fluid) outside the tubes 111. A pair of left header tank 120 and right header tank 130 are located at two end portions of the tubes 111 in the longitudinal direction of the tubes 111 to extend in a direction perpendicular to the longitudinal direction of the tubes 111. In the example of FIG. 1, the left header tank 120 is located at the left end side of the core portion 110 to communicate with the tubes 111 at the one end side in the longitudinal direction of the tubes 111, and the right header tank 130 is located at the right end side of the core portion 110 to communicate with the tubes 111 at the other end side in the longitudinal direction of the tubes 111.

The header tanks 120, 130 are provided with tube insertion holes into which the end portions of the tubes 111 are inserted to be connected to the header tanks 120, 130. The header tanks 120, 130 are brazed to the tubes 111 to communicate with the tubes 111. The longitudinal end portions of each side plate 113 are also brazed to the header tanks 120, 130.

Each of the header tanks 120, 130 is a cylindrical body having an elliptic shape or a circular shape in cross section, and is formed by punching. Two protruding portions 123 extending in a rail shape in the longitudinal direction of the header tank 120 are provided in the side wall of the header tank 120, and are formed integrally with the header tank 120 in the punching. Similarly, two protruding portions 133 extending in a rail shape in the longitudinal direction of the header tank 130 are provided in the side wall of the header tank 130, and are formed integrally with the header tank 130 in the punching.

Two cover members 140 are connected by brazing to two open portions 121 of the header tank 120 so as to close the two open portions 121, and two cover members 140 are also connected by brazing to two open portions 131 of the header tank 130 so as to close the two open portions 131. The cover members 140 extend toward the side plates 113 so as to be brazed to the side plates 113, thereby improving the strength of the condenser 100.

A separator 122 is disposed in the left header tank 120 to partition an inner space into upper and lower space portions. For example, the separator 122 can be connected to the inner wall of the left header tank 120 by brazing. First and second separators 132 a, 132 b are disposed in the right header tank 130 to partition an inner space into upper, middle and lower space portions. For example, the first and second separators 132 a, 132 b are connected to the inner wall of the right header tank 130 by brazing. The second separator 132 b is located in the right header tank 130 at the same height position as that of the separator 122 located in the left header tank 120, and the first separator 132 a is located in the right header tank 130 at a position upper than the second separator 132 b. An inlet-side connector 160 for introducing the refrigerant is connected by brazing to the right header tank 130 at a position upper than the first separator 132 a of the right header tank 130. The inlet-side connector 160 of the right header tank 130 is coupled to a discharge side of a compressor (not shown) of a refrigerant cycle via an inlet-side refrigerant pipe (exterior pipe), and the inlet-side refrigerant pipe is connected to the inlet-side connector 160 to communicate with the upper space portion of the right header tank 130. Therefore, high-pressure refrigerant discharged from the compressor flows into the upper space portion of the right header tank 130 via the inlet-side refrigerant pipe connected to the inlet-side connector 160 of the right header tank 130.

An outlet-side connector 160 is connected and brazed to the left header tank 120 at a lower side of the separator 122, and is connected to an outlet-side refrigerant pipe. Therefore, the left header tank 120 communicates with the outlet side refrigerant pipe via the outlet-side connector 160, so that the refrigerant flowing out of the left header tank 120 flows into an expansion valve (not shown) of the refrigerant cycle through the outlet-side refrigerant pipe.

The receiver 150 is a cylindrical container formed by punching, and is brazed to a side wall of the right header tank 130. Communication paths 151, 152 are provided at two sides of the second separator 132 b, such that the interior of the receiver 150 communicates with the middle and lower space portions of the right header tank 130 through the communication paths 151, 152, respectively.

Next, a refrigerant flow in the condenser 100 will be now described. The refrigerant discharged from the compressor flows into the upper space portion of the right header tank 130 above the first separator 132 a from the inlet-side connector 160 through the inlet-side refrigerant pipe, and then is distributed into a first group of the tubes 111 above the first separator 132 a from the upper space portion of the right header tank 130. While the refrigerant flows through the first group of the tubes 111, the refrigerant is cooled and condensed by performing heat exchange with outside air.

The refrigerant from the first group of the tubes 111 flows into the upper space portion of the left header tank 120, and is U-turned in the upper space portion of the left header tank 120 to flow into a second group of tubes 111 positioned between the first and second separators 132 a, 132 b. While the refrigerant flows through the second group of the tubes 111, the refrigerant is further cooled and condensed by performing heat exchange with outside air.

The refrigerant from the second group of the tubes 111 flows into the middle space portion of the right header tank 130, and the refrigerant in the middle space portion of the right header tank 130 flows into the receiver 150 through the communication path 151. The refrigerant flowing from the communication path 151 into the receiver 150 is separated into gas refrigerant and liquid refrigerant in the receiver 150, and the separated liquid refrigerant in the receiver 150 passes through the communication path 152 to flow into the lower space portion of the right header tank 130 at a lower side of the second separator 132. Then, the refrigerant in the lower space portion of the right header tank 130 is distributed into a third group of the tubes 111 positioned under the second separator 132 b.

The liquid refrigerant is super-cooled while flowing through the third group of the tubes 111, and flows into the lower space portion of the left header tank 120. Then, the refrigerant in the lower space portion of the left header tank 120 flows out from the outlet-side connector 160 to the expansion valve via the outlet-side refrigerant pipe.

Next, the structure of the connector 160 (e.g., inlet-side connector 160 or outlet-side connector 160) will be described. The base structure of the inlet-side connector 160 is the same as that of the outlet-side connector 160. Here, the inlet-side connector 160 located at the right header tank 130 will be typically described.

FIG. 2 is a perspective view showing an entire shape of the connector 160, and FIG. 3 is a cross-sectional view showing the connector 160. As shown in FIGS. 2 and 3, the connector 160 includes a body portion (i.e., second member) 161 and a pipe member (i.e., first member) 163, which are made of a metal material such as aluminum and an aluminum alloy, for example.

As shown in FIGS. 3 and 4, the body portion 161 has a through hole 162 penetrating therethrough in an axial direction, and an enlarged portion 162 c extending from the through hole 162 outwardly in a radial direction. The pipe portion 163 is inserted into the through hole 162 of the body portion 162 to be fitted therein. The pipe portion 163 has a communication path 164 having a first open portion 163 a opened toward the header tank 130 and a second open portion 163 b opened to a side opposite to the header tank 130 in an axial direction. A flat surface 161 a is formed on the body portion 161 at the side of the second open portion 163 b (i.e., a side from which an inlet-side refrigerant pipe 200 is inserted into the body portion 61).

FIG. 4 shows a single unit of the body portion 161. As shown in FIG. 4, the enlarged hole portion 162 c is provided in the through hole 162 at the side of the second open portion 163 b, and the enlarged hole portion 162 c has an open area enlarged from the open area of the other portion of the through hole 162. The body portion 161 has an end portion 162 d for defining the enlarged hole portion 162 c that is positioned at the side of the second open portion 163 b of the pipe portion 163 in the axial direction. The end portion 162 d of the body portion 161 is also used as a flange supporting portion 162 d for supporting a flange portion 182 of the pipe portion 163 in a direction parallel to the axial direction.

The body portion 161 is provided with a screw portion (fastening portion) 162 b into which a bolt is screwed to be fastened therein. The screw portion 162 b is used for fastening the connector to the refrigerant pipe 200 or a jig for detecting a leakage, etc.

As shown in FIG. 3, the pipe portion 163 is formed to define therein the communication path 164 through which the interior of the header tank 120 communicates with the refrigerant pipe 200. A first connection portion 170 is provided in the pipe portion 163 on the side of the first open portion 163 a, and is fitted in an open portion 130 a of the header tank 130. For example, the first connection portion 170 is formed into a cornuted pipe shape (e.g., rectangular pipe shape).

A second connection portion 180 is provided at the side of the second open portion 163 b in the pipe portion 163, and the refrigerant pipe 200 is fitted into the second connection portion 180. For example, the refrigerant pipe 200 is coupled to the discharge side of the compressor. The second connection portion 180 of the pipe portion 163 is formed into a circular pipe shape, for example. The second connection portion 180 of the pipe portion 163 has an open area that is larger than the open area of the first connection portion 170 of the pipe portion 163, in a cross section perpendicular to the axial direction of the communication path 164 of the pipe portion 163.

A flare portion 181 (expansion portion) is provided in the pipe portion 163 at the side of the second open portion 163 b of the communication path 164 to be gradually expanded radially outwardly along the whole circumference as toward the side of the second open portion 163 b (i.e., the side opposite to the first open portion 163 a) in the axial direction.

The second connection portion 180 of the pipe portion 163 is provided with the flange portion 182 that is formed in a circular shape and extends from the flare portion 181 radially outwardly. The flange portion 182 has a flat surface 182 a on the side of the second open portion 163 b. The flat surface 182 a of the flange portion 182 is positioned substantially on the same surface of the flat surface 161 a of the body portion 161.

FIG. 5 is an enlarged view showing the portion A indicated in FIG. 3. As shown in FIG. 5, the flange portion 182 has a radial outer end 182 b in the radial direction, and the end 182 b of the flange portion 182 is spaced from an inner peripheral end 191 of the body portion 161 by a clearance 190. That is, the end 182 b of the flange portion 182 is opposite to the inner peripheral end 191 of the body portion 161 by the clearance 190. Here, the inner peripheral end 191 is formed to define the enlarged portion 162 c shown in FIG. 4. The inner peripheral end 191 is disposed to enclose the end 182 b of the flange portion 182 in a direction perpendicular to the axial direction while the clearance 190 is formed between the inner peripheral end 191 and the end 182 b of the flange portion 182.

An expanding portion 175 is provided in the pipe portion 163 between the first connection portion 170 and the second connection portion 180 in the axial direction. The expanding portion 175 has an open area that is gradually enlarged from the side of the first connection portion 170 to the side of the second connection portion 180.

Next, a method of manufacturing the connector 160 will be described with reference to FIGS. 6 and 7. FIG. 6 shows a method of manufacturing the connector 160.

As shown in FIG. 6, the body portion 161 is formed by pressing, using a plate material that is generally known, at step S100. The pipe portion 163 is formed by pressing, using a pipe material that is generally known, at step S110.

Next, at step S120, the pipe portion 163 is inserted into the through hole 162 of the body portion 161, and is enlarged radially outwardly such that the pipe portion 163 is fitted into the body portion 161. Then, at step S130, the process of forming the connector 160 is ended.

FIG. 7 shows the detail of step S120. As shown in FIG. 7, at step S121, the pipe portion 163 is inserted into the through hole 162 of the body portion 161. Then, the pipe portion 163 is expanded radially outwardly in expending (step S122) such that the pipe portion 163 is fitted into the body portion 161. For example, a jig G1 is inserted into the pipe portion 163, and the pipe portion 163 is expended radially outwardly by pressing of the jig G1 so that a clearance between an outer peripheral surface of the pipe portion 163 and an inner peripheral surface of the body portion 161 is substantially not caused. Therefore, the pipe portion 163 and the body portion 161 are fixed to each other.

Next, a Jig G2 is inserted into the pipe portion 163 at a side of the second open portion 163 b to expand radially outwardly the end portion of the pipe portion 163, so that the flare portion 181 is formed in pressing (flaring step S123). Thereafter, the pipe portion 163 is pressed in the axial direction using a jig G3 from the side of the second open portion 163 b so that the flange portion 182 is formed in pressing of step S124.

With the above manufacturing process, the surface direction of the flat surface 182 a of the flange portion 182 corresponds to the surface direction of the flat surface 161 a of the body portion 161. That is, the flat surface 182 a of the flange portion 182 is positioned substantially on the same surface as the flat surface 161 a of the body portion 161.

Then, the pipe portion 163 is fitted into the body portion 161 so that the connector 160 is finished as shown at step S130 in FIG. 6.

Next, an assembling operation of the refrigerant pipe 200 and the header tank 130 of the heat exchanger 100 by using the connector 160 will be described with reference to FIG. 3. First, the first connection portion 170 of the connector 160 is inserted into the tank open portion 130 a of the header tank 130, and is fitted into the tank open portion 130 a of the header tank 130. Thus, the first connection portion 170 of the connector 160 is fixed to the header tank 130 by brazing.

Next, the refrigerant pipe 200 is inserted into the second connection portion 180 of the connector 160. The refrigerant pipe 200 may be used for supplying the refrigerant discharged from the compressor into the header tank 130 of the heat exchanger 100.

When the refrigerant pipe 200 is inserted into the second connection portion 180, a circular seal member (e.g., O-ring) 210 located at a side of a tip end portion of the refrigerant pipe 200 is guided by the flare portion 181 of the second connection portion 180, and is inserted into the second connection portion 180. With this, the O-ring 210 is located between an outer peripheral surface of the refrigerant pipe 200 and an inner peripheral surface of the second connection portion 180 to seal a clearance therebetween.

A connector 300 on a side of the refrigerant pipe 200 is disposed such that a through hole 301 of the connector 300 and the screw portion 162 b of the body portion 161 of the connector 160 are lined. Therefore, the through hole 301 of the connector 300 and the screw portion 162 b of the body portion 161 of the connector 160 communicate with each other. Then, a bolt (not shown) is screwed to the through hole 301 and the screw portion 160, thereby fixing the connector 300 and the connector 160 to each other. Accordingly, the refrigerant pipe 200 is fixed to the connector 160, and the refrigerant pipe 200 can be assembled to the header tank 130 using the connector 160.

According to the first embodiment, the connector 160 includes the body portion 161 and the pipe portion 163 which are formed separately. The pipe portion 163 includes the first and second connection portions 170, 180 that are formed by pressing. Because the first and second connection portions 170, 180 are formed in the pipe portion 163 without using a cutting process, manufacturing efficiency of the connector 160 can be improved thereby improving the manufacturing efficiency of the heat exchanger 100. Furthermore, when a large amount of the connectors 160 are manufactured, the product cost can be effectively reduced as compared with a case where the first and second connection portions 170, 180 are formed in the connector 160 by cutting process.

In the first embodiment, the second connection portion 180 of the pipe portion 163 is provided with the flare portion 181. Thus, when the O-ring 210 of the refrigerant pipe 200 is inserted into the second connection portion 180, the insertion movement of the O-ring 210 is guided by the flare portion 181. Accordingly, the O-ring 210 can be easily inserted between the refrigerant pipe 200 and the second connection portion 180 of the pipe portion 163 to seal therebetween.

In the first embodiment, the surface direction of the flat surface 182 a of the flange portion 182 of the connector 160 corresponds to the surface direction of the flat surface 161 a of the body portion 161. That is, the flat surface 182 a of the flange portion 182 is positioned substantially on the same surface as the flat surface 161 a of the body portion 161. Therefore, a clearance between the connector 160 and the connector 300 of the refrigerant pipe 200 can be sufficiently reduced, thereby a contact state between the connector 160 and the connector 300 of the refrigerant pipe 200 can be improved.

When the clearance between the connector 160 and the connector 300 of the refrigerant pipe 200 becomes larger, foreign material such as a corrosion liquid can be easily entered into a portion near the O-ring 210, as shown by the arrow “a” in FIG. 3. In this case, the O-ring 210 may be corroded by the corrosion liquid, and the sealing performance of the O-ring 210 may be deteriorated.

In contrast, in the first embodiment, it is difficult for a corrosion liquid from entering to the area around the O-ring. In FIG. 3 of the first embodiment, the clearance between the connectors 160 and 300 is indicated for only the convenience of the explanation.

According to the first embodiment of the present invention, the clearance 190 is provided between the end 182 b of the flange portion 182 and the inner peripheral end 191 of the enlarged hole portion 162 c. If the clearance 190 is not provided, the end 182 b of the flange portion 182 may contact the inner peripheral end 191 of the enlarged hole portion 162 c due to the dimension differences of the pipe portions 163, when the flange portion 182 is formed. In this case, the flange portion 182 may be bent in the pressing at step S124, and thereby a clearance may be easily caused between the connectors 160 and 300. In contrast, because the clearance 190 is set between the end 182 b of the flange portion 182 and the inner peripheral end 191 of the enlarged hole portion 162 c, it is difficult for the end 182 b of the flange portion 182 to contact the inner peripheral end 191 of the enlarged hole portion 162 c. Furthermore, because of the clearance 190 between the end 182 b of the flange portion 182 and the inner peripheral end 191 of the enlarged hole portion 162 c, corrosion liquid can be stored in the clearance 190 even if the corrosion liquid enters between the connectors 160 and 300. Accordingly, the clearance 190 can restrict the corrosion liquid from flowing to the area near the O-ring 210.

Second Embodiment

A second embodiment of the present invention will be now described with reference to FIGS. 8 and 9. In the second embodiment, a connector 160 is configured such that the pipe portion 163 is difficult to rotate relative to the body portion 161. FIG. 8 is a sectional view showing a part of the body portion 161 and the pipe portion 163, and FIG. 9 is a perspective view showing the body portion 161.

In the second embodiment, four protruding portions 230 are provided at the pipe portion 163 to protrude radially into the body portion 161. That is, the protruding portions 230 protrude radially outwardly from the inner peripheral surface of the body portion 161 into the body portion 161. In FIG. 8, two protruding portions 230 are indicated.

As shown in FIG. 9, four recess portions 245 are provided in the inner peripheral surface of the body portion 161 at positions corresponding to the positions of the protruding portions 230, such that the protruding portions 230 of the pipe portion 163 are fitted into the recess portions 245, respectively. Therefore, it is difficult to rotate the pipe portion 163 with respect to the body portion 161. Accordingly, the pipe portion 163 can be maintained at a predetermined position, relative to the body portion 161.

In the second embodiment, the protruding portions 230 of the pipe portion 163 and the recess portions 245 on the inner peripheral surface of the body portion 161 are set at an axial position offset from an arrangement area H of the O-ring 210 in an axial line S, as shown in FIG. 8.

When the protruding portions 230 of the pipe portion 163 are formed by pressing, the elastic force at the position of the pipe portion 163, where the protruding portions 230 are formed, is lower than the elastic force at the other position of the pipe portion 163. Thus, if the O-ring 210 is located close to the low elastic force portion of the pipe portion 163, the sealing performance of the O-ring 210 is deteriorated, thereby deteriorating the sealing performance between the second connection portion 180 and the refrigerant pipe 200.

In the second embodiment, because the protruding portions 230 are set at the position shifted from the arrangement area H of the O-ring 210 in a direction of the axial line S, the sealing performance of the O-ring between the second connection portion 180 and the refrigerant pipe 200 can be improved.

In the second embodiment, plural protruding portions 230 other than four or a single protruding portion 230 may be provided in the pipe portion 163. In this case, one recess portion 245 or plural the recess portions 245 having the same number as that of the protruding portions 230 can be provided in the body portion 161 to correspond to the single protruding portion 230 or the plural protruding portions 230. Alternatively, the protruding portions 230 may be located at the body portion 161, and the recess portions 245 may be provided at the pipe portion 163.

Other Embodiments

Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art.

For example, at step 110 of FIG. 6, the first connection portion 170 is formed into a cornuted shape (e.g., rectangular pipe shape) by pressing. However, in a state of the connector 160 before the flare portion 181 and the flange portion 182 are formed, the first connection portion 170 of the pipe portion 163 may have a circular shape. That is, after the flare portion 181 and the flange portion 182 are formed, the first connection portion 170 may be formed into the cornuted shape (e.g., rectangular pipe shape).

In the above-described embodiments, the two header tanks 120 and 130 are located at two sides of the core portion 110 to distribute the refrigerant into the tubes 111 and to join the refrigerant from the tubes 111. However, one header tank may be located at one side of the core portion 110 to distribute the refrigerant into the tubes 111 and to join the refrigerant from the tubes 111. Alternatively, one of the header tanks 120, 130 can be used as a tank for distributing the refrigerant into the tubes 111, and the other one of the header tanks 120, 130 can be used as a tank for joining the refrigerant from the tubes 111.

In the above-described embodiments, the heat exchanger is used as the condenser 100 having plural groups of refrigerant flows. However, the present invention can be applied to a heat exchanger in which the refrigerant flows through all the tubes 111 in one way without being U-turned.

The present invention can be applied to various types of heat exchangers without being limited to the condenser 100. For example, the heat exchanger may be a radiator, an inner cooler, a heater or an evaporator.

Such changes and modifications are to be understood as being within the scope of the present invention as defined by the appended claims. 

1. A heat exchanger comprising: a plurality of tubes in which a fluid flows, the tubes being arranged in parallel with each other; a header tank located at one end side of the plurality of tubes in a longitudinal direction of the tubes to distribute the fluid into the tubes and to join the fluid from the tubes; and a connector that includes a first member configured to define a communication path through which a tank open portion of the header tank communicates with an interior of an exterior pipe, and a second member to which the first member is fixed, wherein: the first member and the second member are fixed to each other after being separately formed by pressing; the second member has a fastening portion through which the connector is fastened to the exterior pipe; and the first member includes a first connection portion that is fitted into the tank open portion at one open side of the communication path, and a second connection portion fitted to an open portion of the exterior pipe at other open side of the communication path.
 2. The heat exchanger according to claim 1, wherein the second member has a through hole into which the second connection portion of the first member is fitted by expanding the second connection portion to the first member.
 3. The heat exchanger according to claim 1, wherein the first connection portion of the first member is brazed to the tank open portion of the header tank to be fixed to the tank open portion of the header tank.
 4. The heat exchanger according to claim 1, wherein: the first connection portion of the first member is a cornuted pipe; and the second connection portion of the first member is a circular pipe.
 5. The heat exchanger according to claim 1, wherein: the second connection portion of the first member is located to be fitted into the open portion of the exterior pipe; the second connection portion includes a flare portion at an end portion in an axial direction; and the flare portion extends radially outwardly as toward to the other open side of the communication path in the axial direction.
 6. The heat exchanger according to claim 5, wherein: the second connection portion of the first member further includes a flange portion extending outwardly in a radial direction from the flare portion; and the second member has a flange supporting portion configured to support the flange portion in a direction parallel to the axial direction.
 7. The heat exchanger according to claim 6, wherein: the flange portion has a flat surface at the other open side of the communication path in the axial direction; the second member has a flat surface at the other open side of the communication path in the axial direction; and the flat surface of the flange portion has a surface direction that corresponds to that of the flat surface of the flange portion.
 8. The heat exchanger according to claim 7, wherein: the second member has an inner peripheral end surface at the other end side in the axial direction, the inner peripheral end surface being located to enclose the flange portion of the second connection portion of the first member in a direction perpendicular to the axial direction; and the flange portion has a radial outward end portion that is opposite to the inner peripheral end surface of the second member and is spaced from the inner peripheral end surface of the second member by a clearance.
 9. The heat exchanger according to claim 1, wherein the second member has an inner peripheral surface portion for defining the through hole, the heat exchanger further comprising: one of a recess portion and a protruding portion, provided at the inner peripheral surface portion of the second member; the other one of the recess portion and the protruding portion, provided at an outer peripheral portion of the first member; and the protruding portion is fitted into the recess portion.
 10. The heat exchanger according to claim 9, further comprising a seal member located at the inner peripheral surface portion of the second connection portion of the first member to seal between the inner peripheral surface portion of the second connection portion and the exterior pipe; and the one of the recess portion and the protruding portion is located at a position shifted from the seal member in the axial direction.
 11. The heat exchanger according to claim 1, wherein: the exterior pipe is for supplying the fluid to the header tank or for discharging the fluid from the header tank; and the tubes are arranged such that the fluid flowing in the tubes is heat exchanged with an exterior fluid outside the tubes.
 12. A method of manufacturing a heat exchanger having a connector for connecting a header tank with an exterior pipe, the method comprising: forming the header tank to be connected to one end side of a plurality of tubes in a longitudinal direction of the tubes; and forming a connector, wherein the forming of the connector includes: forming a first member having a first connection portion and a second connection portion by pressing; forming a second member having a through hole by pressing; inserting the second connection portion of the first member into the through hole and expanding the second connection portion by using a jig to the first member, forming a flare portion by pressing at an end portion of the second connection portion of the first member, and forming a flange portion at a position radially outside of the flare portion by pressing; and fitting the first connection portion of the first member to a tank open portion of the header tank.
 13. The method of manufacturing a heat exchanger according to claim 12, wherein the first connection portion of the first member is brazed to the tank open portion of the header tank to be fixed to the tank open portion of the header tank.
 14. The method of manufacturing a heat exchanger according to claim 12, wherein the first connection portion of the first member is formed into a cornuted pipe, and the second connection portion of the first member is formed into a circular pipe.
 15. The method of a heat exchanger according to claim 12, further comprising fitting the second connection portion of the first member into an open portion of the exterior pipe.
 16. The method of a heat exchanger according to claim 12, wherein: in the forming of the second member, a flange supporting portion is formed; and the flange support portion supports the flange portion in a direction parallel to the axial direction when the first member is fitted into the second member.
 17. The method of a heat exchanger according to claim 12, wherein: the flange portion is formed by pressing to have a flat surface; the second member is formed to have a flat surface; and the first member is fitted to the second member such that a surface direction of the flat surface of the flange portion corresponds to a surface direction of the flat surface of the flange portion.
 18. The method of a heat exchanger according to claim 12, wherein: the first member is fitted to the second member such that an inner peripheral end surface of the second member encloses the flange portion of the second connection portion of the first member in a direction perpendicular to the axial direction, and the flange portion has a radial outward end portion that is opposite to the inner peripheral end surface of the second member and is spaced from the inner peripheral end surface of the second member by a clearance. 